54 Aurigae is resolved into two visible components, of magnitudes 6.22 and 7.82, separated by0.8″. The double was discovered in 1843 when the separation was only0.7″.[10] There is no separate measure of the parallax of the secondary, but it shares a commonproper motion with the brighter star[11] and they are assumed to form abinary.[10] The spectral class B7 III is assigned to the brighter of the pair, indicating a hotgiant star, although it has also been given as B7/8 III/V, suggesting it may be amain sequence star.[12] Most sources can't give a separatespectral classification for the fainter star, but it has been listed as DA1/K4V, indicating it is either awhite dwarf orred dwarf.[13]
^Cucchiaro, A.; et al. (October 1977), "Spectral classification from the ultraviolet line features of S2/68 spectra. II - Late B-type stars",Astronomy and Astrophysics Supplement Series,30:71–79,Bibcode:1977A&AS...30...71C.
^abMason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog",The Astronomical Journal,122 (6):3466–3471,Bibcode:2001AJ....122.3466M,doi:10.1086/323920,ISSN0004-6256.
^Clausen, J. V.; Jensen, K. S. (1979), "Classification Based on 102/A/Mm Objective Prism Spectra",IAU Colloq. 47: Spectral Classification of the Future,9: 479,Bibcode:1979RA......9..479C.
^Pickles, A.; Depagne, É. (2010), "All-Sky Spectrally Matched UBVRI - ZY and u′ g′ r′ i′ z′ Magnitudes for Stars in the Tycho2 Catalog",Publications of the Astronomical Society of the Pacific,122 (898): 1437,arXiv:1011.2020,Bibcode:2010PASP..122.1437P,doi:10.1086/657947,S2CID54678796.
